Shop Windows to the Universe

White Dwarfs Stars

The planetary nebula NGC 2440 contains one of the hottest white dwarf stars
known. The white dwarf can be seen as the bright dot near the picture's
center.
Click on image for full size (20K JPEG)Image courtesy of H. Bond (STSci), R. Ciardullo (PSU), WFPC2, HST, NASA.

Shop Windows to the Universe Science Store!

Cool It! is the new card game from the Union of Concerned Scientists that teaches kids about the choices we have when it comes to climate change—and how policy and technology decisions made today will matter. Cool It! is available in our online store.

Windows to the Universe Community

News

Opportunities

You might also be interested in:

The basic Hydrogen fusion cycle involves four Hydrogen nuclei (protons) and two electrons and yields a Helium nucleus, two neutrinos and six photons. This process occurs in three steps: the first one is...more

Fusion in the core of the stars is achieved when the density and temperature arising from the gravitational pressure are high enough. There are different fusion cycles that occur in different phases of...more

Neutron capture can occur when a neutron approaches a nucleus close enough for nuclear forces to be effective. The neutron is captured and forms a heavier isotope of the capturing element. When the new...more

IMF stands for Interplanetary Magnetic Field. It is another name for the Sun's magnetic field. The Sun's magnetic field is enormous and is carried by the solar wind. The solar wind and magnetic field are...more

Nuclear fusion is a process where two or more nuclei combine to form an element with a higher atomic number (more protons in the nucleus). Fusion is the reverse process of nuclear fission. Fusion of light...more

The theory of relativity states that no particle can travel at the speed of light in a vacuum. However, light travels at lower speeds in dense media, like water. A particle traveling in water must have...more

Neutrino interactions with matter are extremely rare, making detection difficult. Neutrino detectors are typically large tanks filled with a fluid that reacts to the passage of neutrinos. To take advantage...more